Net income increased to $722 million, or 43 cents a share, from $442 million, or 28 cents a share, a year earlier, the Foster City, California-based company said today in a statement. Earnings, excluding some items, of 48 cents a share fell short by 2 cents of the average of 24 analysts' estimates compiled by Bloomberg. Revenue rose 11 percent to $2.53 billion.

Gilead shares rose 79 percent last year, the most since 1995, as sales of HIV drugs increased and optimism built about its experimental hepatitis C therapies leading a $20 billion market. Sales of the treatments in the U.S. alone may reach $6.5 billion in 2014 or 2015 after it wins regulatory clearance, Mark Schoenebaum, an analyst with International Strategy & Investment Group in New York, said in a note to clients in March.

"Gilead could utterly annihilate 2014 consensus numbers," Schoenebaum wrote in his note. "I have a hard time believing the stock doesn't continue to go higher. And in a worse case, stock probably won't go down."